CLEVELAND, OHIO — Terror gripped an entire city on May 9, 2003. Violence had erupted without warning.

Scenes unfolded live on television as camera crews gathered outside one building. Once world-famous for it’s distinctive architecture, the School of Management at Case Western Reserve University in Cleveland Ohio was now becoming famous for something much more sinister — something camera crews outside could not see — a shooting.

The day had started out so calmly.

George Klippel, school facilities manager: It was a beautiful summer day. The skies were blue. The sun was out. It was great.

Exams over. Commencement was around the corner. It was a quiet Friday afternoon at the end of the school-year

Klippel: Most of the students were gone, they were out doing things.

George Klippel, the school’s facilities manager, was finishing up a classroom inspection on the fourth floor.

Norman Wallace, a first year MBA student, was chatting with friends about internships. It was going to be a busy summer.

Sheila Young: He had a lot going on. He was talking about like the future. You know, he was excited

Shawn Miller, an administrator in the school’s computer lab, was heading out to a local bar.

Shawn Miller: We’re having a party at Jillian's that night. You know, a little pool. Some hors d’oeuvres.

But for these three men, just minutes away from leaving the management school, the sound of smashing glass and a volley of automatic gunfire signalled the beginning of a seven hour fight to stay alive.

Klippel: I really could not believe what I heard. It just didn’t make any sense at all.

Another question haunting the crowd outside the building: how many people were trapped inside? Since it was the end of the school year maybe only a few people were around and potentially at risk. But no one knew for sure. For hours, the only information reaching the crowd was the sound of sporadic gunfire echoing in the streets

Klippel: It was just like a crack—real loud.

4 p.m. Inside the building, the sound of gunfire was deafening. George Klippel, the facilities manager, ran down stairs to the third floor, heading for the fire exit and escape, but he stopped when he came to an office with a window overlooking the atrium. The former marine could see a gunman on the floor below him.

Klippel: The first thing I saw was a flack jacket. I thought for a minute I was looking at another marine that was in combat gear.

Klippel climbed onto the desk to get a better view and dialed 911, becoming one of the first people to give police a better idea of what was going on inside the building.

Klippel (911 call): We have a gunman in the building who has opened fire. He has a helmet on. A green military helmet.

Then Klippel noticed what the gunman was looking at. He told the 911 operator a man was lying motionless on the ground floor.

Klippel: There’s a man down. A man down right outside the cafe.

911: How many people are down, sir?

Klippel: I can only see one but I think there’s more.... Oh, man. That guy hasn’t even moved one muscle....

911 operator: Oh, my God.

For the first time Klippel realized how vulnerable he was, pressed up against a window in plain sight of the shooter. He dove under the table he had been standing on.

Klippel: Another shot fired.

911: Another shot fired.

Three floors below him, in the basement, Shawn Miller, the computer lab administrator, was standing outside the computer lab with three colleagues. They’d heard gunfire but didn’t know what to do.

Shawn Miller: All of a sudden there’s this guy standing at the end of the hallway with a flak jacket. We see a gun being raised and we all just scatter.

Miller ran back into the computer lab, a bullet tearing through the door right behind him.

Then everyone started running, knocking over chairs to get to a room at the back of the lab only accessible by ID card. But Miller’s co-worker couldn’t get his card to work.

Miller: And we’re pushing on that door. And finally he gets it and the door opens and we just spill into the room.

As the door locked behind them, the group scrambled for cover in cubicles, behind chairs and under desks.

Miller: He shoots through the wall. I mean these are particle board walls. Bullets went right through them.

Caller: We heard another shot a moment ago.

Someone in the computer lab with Miller called 911. The operator told the group to hide the best they could.

Caller: There’s a window out to the lab.

911: OK... get down below that window.

Caller: We are.

Then Miller says he heard the gunman try the door handle. It didn’t budge and suddenly everything fell quiet.

4.20 p.m. Just twenty minutes after the shooting had started, an eight man-SWAT team from Cleveland’s police department arrived.

Bill Safos: They’re jumping out of their cars. Right away they’re putting on their body armor, I’ve never seen that many SWAT officers ever.

Not really sure what was going on inside the building or even if there was more than one gunman, the SWAT team advanced inside, under the gaze of an entire city. Onlookers standing on the street, families at home glued to their televisions waited to see what would happen and what the final cost of this bloody rampage would be.

7 p.m.Three hours after the ordeal began, a sign of hope.

People watching live coverage at home saw a dramatic rescue. Two women were rushed to safety.

But there was no sign the shooter had been cornered. The police made a plea on television, asking the gunman to pick up the phone.

George Klippel, the facilities manager, was still feeding information to police. He told the 911 operator he could hear gunshots right outside his door.

Klippel: More shots.

911 operator: More shots fired.

Klippel: Oh, God.

And the 911 operator told Klippel what he could not see. Police had pieced together a frightening picture from other 911 calls. Nearly 100 hostages like him were dotted around the building hiding for their lives.

911: We still have no idea why this guy’s doing this. We don’t know if he’s a student or a —

Klippel: Yeah. I think he looked young.

911: Sure seems like he’s got an unending supply of ammunition.

Three floors below George Klippel: complete silence in the computer lab where Shawn Miller, was hiding. No one wanted to attract the attention of the gunman.

Miller’s mind started racing. Who would do something like this? Who could the gunman be? One person came to mind—but he quickly dismissed the thought.

Miller: That’s kind of crazy, I mean to go shoot up a building.

As time went on, Miller started thinking about death

Miller: I’m wondering you know, this is the basement? Are they setting up explosives down here so they can blow the building? I’m thinking, “Well we’re probably pretty close to the center of it. So it’ll be fast.”

George Klippel, the school’s facilities manager was still hiding in a third floor office. He couldn’t hear shooting anymore and feared the SWAT team had forgotten to come rescue him.

Klippel: They’re going to make it up to the third floor eventually, right?

911: Yes they will.

Klippel: You promise?

911: I promise you. I would not lie to you.

George Klippel: You do feel isolated. You feel alone. Most of my thoughts were about family and friends. And just want to see my wife and my children again.

10 p.m. Hours after the shooting began, Klippel heard the SWAT team pound on his door.

Klippel: First thing is “Hands on your head.” There’s a gun right in your face. But you know, it was great to see them.

Less fortunate was the family of the man who Klippel had seen lying on the floor.

It was 30-year old Norman Wallace—the first year MBA student.

Sheila Young: I actually got the call on my cellphone. I don’t know if I screamed or I just broke down.

Norman’s family crowded around their television in disbelief hoping there’d been some terrible mistake until they saw it for themselves—their brother’s body being carried out of the building.

David Wallace: We didn’t know it was Norman until we saw the shoe.

Corrie Wallace: Shoe and his pants. I lost it.

Norman’s younger brother collapsed, flashbacks of his childhood playmate rushing before his eyes.

Corrie Wallace: I kept telling my brothers… I can’t get this pain outta my head. I can’t, I don’t know what to do.

Norman’s killer was finally cornered by the SWAT team more than seven hours after he’d first opened fire. He’d taken one life, seriously wounded two others and held 90 people hostage. And this was the face of the man who had caused so much pain.

Klippel: I was shocked. I mean he looked really timid. He looked really shy.

Bill Safos: His appearance. He didn’t look like the type of person that could do this.

Sheila Young: Just the words hurt. Just saying that “somebody’s gone.”

The sister of Norman Wallace couldn’t bear to say it out loud. Her high-spirited, loving 30-year-old brother was dead, gunned down in the halls of Case Western Reserve University.

Sheila Young: It was like something broken. Something broken.

What was broken was her family. It had not been an easy childhood for Norman and his ten brothers and sisters growing up poor in Youngstown Ohio. Through it all, they said, it was Norman who held them together

Corrie Wallace: There was something about Norman. He just rubbed off on you. It was... he affected you with his kindness, his love. The joy he had…

And Norman was ambitious. After a few years working as a mortgage broker and a day trader he applied to Case Western’s management school.

Corrie Wallace: He said, “I’m tired of being at a desk. I wanna do something different. I wanna help people.”

But Norman would never get a chance to fulfill his dream. Instead, he crossed paths with a stranger who shot him in the heart.

Prosecutor’s opening statement: This is the tale of two men — one who you’ll find out is very warm and caring, another one you’ll hear is cold and calculated.

That other man was a former student at the management school—62-year-old Biswanath Halder. And on November 28th 2005 , Halder went on trial for the murder of Norman Wallace and the attempted mass murder of other people he’d shot at when he stormed into the university building.

Prosecutor: He wanted to kill as many people or hurt as many people as he possibly could.

And the prosecutor’s star exhibit was this: A videotape. Biswanath Halder’s alleged seven-hour campaign of terror had been captured on tape by the university’s security cameras. Now the prosecutor promised the jury, and the Cleveland community at large, that they would finally see for themselves what happened inside the building that day.

But before the jury would see the videotape of the day itself, the prosecutor wanted them to hear how carefully Halder had planned his crime.

Prosecutor: We wanted to make sure that they understood that there was a method to this.

The prosecutor listed for the jury the careful preparations Halder had made.

In November 2001, more than a year before the shooting he bought a Cobray M-11 semi-automatic. A month later, he bought a 9mm Ruger from a local gunstore and started hoarding boxes of ammunition. Four days before the shooting Halder rented a getaway car. And finally the night before the attack, the prosecutor said Halder carried out one last check.

The manager of a local gun shop testified that Halder brought in his 9mm Ruger.

Gunstore manager: He come in. It was just about closing time in the store. He had taken the weapon apart and could not get it back together.

Prosecutor: So why would he come to you?

Manager: He wanted me to show him how to reassemble it.

A little after 3 p.m. It’s May 9th 2003.

The videotape tells the story as Norman Wallace stands at the school reception desk in the lobby by the front door. Classes are over for the year but Norman has dropped into school to put the finishing touches on a graduation party for his friends.

This is Halder as he walks calmly up to the school’s back-door. He’s wearing an army helmet and in his black backpack is the re-assembled Ruger, his Cobray M11 and a mallet.

Halder takes the mallet out of his backpack and starts smashing at the back-door of the building—again and again, using all his strength.

Halder climbs through the hole he has made and walks across the school atrium, toward the lobby. He is carrying the assault rifle in his right hand, according to the prosecutor, looking for someone to kill.

By this time, Norman Wallace has left the reception desk to join some friends in the lobby to chat about basketball and summer internships. He is the first person who will cross paths with Biswanath Halder.

Jonathan Brickner (in court): I saw Norman take a couple of steps out to get a better view of this person.

Norman walks past the pillar and then suddenly turns on his heels pursued by the gunman.

Brickner: All of a sudden I saw a gun come up. Bang!

Video from another security camera shows what happened next. People scatter at the sound of gunfire. The school receptionist hides under her desk. And Norman Wallace falls to the ground, mortally wounded. He’s been shot at point-blank range.

The same surveillance camera captures video of Norman’s friend flipping over a table, diving behind it for cover. And without hesitating, Halder moves toward the table trying to shoot him.

Jonathan Brickner: I’m thinking life flashing before my eyes... thinking have I lived the best life I know how, thinking that it’s surely over at this point.

While Norman’s friend hides behind the table, Halder walks past his dying victim toward the school reception desk in the lobby.

Lee Nagel: I distinctly remember his eyes.

The man walking towards Halder in the white T-shirt and jeans was the prosecutor’s next witness. Lee Nagel, a law student, hadn’t heard the gunshots and didn’t notice Norman’s body lying just a few feet away. He had no idea what was going on until Halder aimed his gun.

Lee Nagel: I noticed him pointing it at me and the snapping noise, it sunk in when he cleaned out the action and a shell was ejected.

The video shows the law student fleeing as Halder’s gun jams. Another student in a blue shirt notices what’s happening and ducks out of the way.

Then you can see campus police arriving on the scene. They throw themselves at the wall, scrambling for cover as Halder starts shooting at them

Halder was firing so aggressively, according to Sergeant Daniel Stein, that he and his partner retreated outside behind some parked cars to check each other for bullet wounds

And then, the prosecutor argued, Halder essentially took control of the building. More security cameras in the school’s stairwells show him striding between floors. And while he hunts for more victims, dozens of people look for somewhere to hide. People like one woman missed the gunman by seconds. Another man who was not so lucky. Video shows him running out of the building clutching his wound. Halder had shot him as he fled down a second floor corridor.

The prosecutor showed the jury an architect’s model of the building. Each red cross marked on the floor plan represented a person who was trapped that day. 93 people hid under desks, in closets, behind computers. They would be there for hours.

Carleen Bobrowski-Henderson: My first thought was how it was going to feel when I got shot. I kicked my shoes off because I knew I had to run (cries).

Amanda Nicol: I prayed for seven hours and I didn’t know what to do because I couldn’t get out.

Some of the witnesses also relived farewell phone calls to loved ones.

Dr. Melvin Smith: I did call my wife and let her know, “I’m trapped in the building, here. I’m okay right now. I asked her to let me talk to both my sons because I didn’t know if it might be the last time that I might get a chance to talk to them.”

Stafford: What made the difference between whether someone lived or died that day?

Prosecutor: Whether they ran.

For Professor Avi Dor there’s no way to run. He is confined to a wheelchair because he suffers from multiple sclerosis. He says a split second decision saved his life.

Prof. Avi Dor: The shooter had caught up with me and fired, fired at me and I just sort of slouched back.

Dor showed the jury how he faked his own death, staying like that until he heard Halder walk away.

Then Dor testified that he rolled into an open office and fell to the floor—terrified.

One woman was shot. Professor Susan Helper came face to face with Halder in the second floor corridor. She slammed her office door just as he fired his gun at her

Susan Helper: The bullet came through the door I think before the door was even all the way shut and hit me in the chest right here.

Prosecutor: This gun here?

But the door had dulled the impact of the cop-killer bullet almost like a shield. When the bullet hit the professor in the chest, it bounced off her collar-bone and onto the floor.

Susan Helper: I just felt this kind of powerful pop but I don’t think it knocked me down.

The prosecutor asked the professor to put on the shirt she had been wearing that day. The bullet hole was clearly visible

Rob Stafford: And where is the bullet hole?

Prosecutor: It was right where her heart is. She should have died that day. She should have died.

Surprisingly only one man was killed that afternoon. But many others would have been, argued the prosecutor, if the SWAT team hadn’t arrived. And when it did, Halder turned from being the hunter, into the hunted.

Officer Bill Johnson: One of my teammates came running through the locker room and stated that there was several gunmen inside Case Western and there were people shot.

The prosecutor wanted the jury to hear from members of the SWAT team who’d risked their lives trying to catch Biswanath Halder.

Rick Bell: It is clear to the police that someone is raining bullets down on them—that this person is taking vantage points in order to kill them. And this is a military-style operation.

And once again, the jury was able to see for themselves what had happened because it had been caught on tape.

Officer Johnson: The silence when we first went in that building… I can’t even describe it.

The tape shows Officer Bill Johnson and the rest of the Cleveland SWAT team gingerly entering the building.

Officer Johnson: I looked off to my left and there lay the body of Norman Wallace.

Rob Stafford, Dateline correspondent: Any sign of life?

Officer Johnson: No.

Johnson and his partner dragged Norman’s body to safety. Moments later, gunfire erupted behind them from an upper floor. They had nowhere to hide.

Officer Johnson: My heart was beating so hard that I could feel it bouncing off the inside of my tactical vest.

That was the beginning of what Johnson described as a cat-and-mouse game between the gunman and the SWAT team that went on for hours.

Stafford: So the shooter is hiding and then popping up and firing at you?

Officer Johnson: Yes, with what he knew about weapons, it was his building for awhile.

Halder even used the elevators as a decoy. When he wanted to change positions, Johnson said Halder would send the elevators down to the lobby. The SWAT team would train their firepower on the opening doors.

Stafford: You expect to see a gunman and take fire?

Officer Johnson: Yes.

Stafford: And what’s inside the elevator?

Officer Johnson: They were empty.

Stafford: Do you feel he’s taunting you?

Officer Johnson: At a certain point, yes.

But the SWAT team advanced on the shooter, jamming the elevator doors with furniture and firing back every time they got a glimpse of the gunman.

Officer Johnson: He was trying to kill all of us. And along with how many other people that were in that building he was trying to kill. Yeah, we were looking for a way to subdue him.

Stafford: A clean shot?

Johnson: Yes.

Stafford: And you’d take it if you have it?

Johnson: Yes.

Eventually, back-up arrived for Johnson and his team, officers from the sheriff’s department, another SWAT team from across county lines, and even the FBI. The units fanned out and used their superior firepower to push Halder higher into the building. Along the way, Johnson says he noticed trails of blood— possibly the shooter’s— on the walls, as well as live rounds of ammo on the floor, a sign the shooter’s weapon was malfunctioning.

Johnson: We all knew right away that the male’s gun was starting to jam on him.

Then, as suddenly as it began, it was over. Seven hours after he fired his first shot, Biswanath Halder surrendered in this fifth floor classroom. He’d been wounded in the gun battle—hit once in the shoulder and once in the stomach.

Johnson: I was kinda dumbfounded when I looked into this male’s face and saw an older gentleman there who at that point looked pretty beaten and worn out.

Why had 62-year old Biswanath Halder, a former student, unleashed such violence on Case Western Reserve?

Prosecutor: This man had a vendetta. He was very angry and he was very arrogant.

The prosecutor argued Halder was nothing more than a vigilante, exacting a meticulously planned revenge for what he believed one man had done to him. That man had been hiding in the building during the attack. It was computer lab administrator, Shawn Miller.

Stafford: The shooter is identified as Biswanath Halder.

Shawn Miller, computer lab administrator: Right.

Stafford: What goes through your mind when you hear it?

Miller: I feel guilty.

Guilty, he says, because the shooting was the climax of a feud Halder had waged against him for three years. Even now that Halder is in custody it’s hard for Miller to believe it will ever end.

Miller: I’ve had sleepless nights not being able to sleep at night because I’m afraid that you know, someone out there is going to finish Halder’s work for him.

Shawn Miller first met Halder in the management school’s computer lab where Miller was the supervisor. Halder would spend up to twelve hours a day there and they didn’t get along.

Miller: Eccentric, rude, unpleasant. I mean, you know, it wasn’t like just I had that. I mean, believe me, he was universally reviled.

A couple of times Miller had to discipline Halder for breaking the rules. He says Halder just ignored him.

Miller: I mean he wouldn’t react. It was like, he would just sit there and stare at you.

But in July 2000, Halder became openly angry with Miller. Someone had hacked into his computer and deleted thousands of files and he was convinced Miller was the culprit. Those files he said were the groundwork for a multi-million dollar business. The hacker had also left behind a number of offensive messages in the guestbook on Halder’s Web site.

Stafford: Halder is described as “Wearing tighty whitey shorts. This guy makes a living out of creeping people out. He’s a loon.”

Miller: It describes him in a very mocking way. But it’s not like it’s an inaccurate portrayal.

Stafford: He was creeping people out?

Miller: He was a creepy guy.

Miller denied again and again that he was the hacker but Halder didn’t believe him. Infuriated, Halder complained to Case Western demanding that Miller be punished but the university referred the matter to police. When the police dropped the case for lack of evidence, Halder still wasn’t satisfied. So he sued Miller.

Stafford: Did you hack into his computer?

Miller: No.

Stafford: You didn’t do this?

Miller: No.

At the end of April 2003, Halder’s lawsuit was thrown out of court but he wasn’t done. Convinced now that Miller and the university had conspired to harm him, Halder picked up a gun, the prosecutor said, with a mission in mind. He was intent on finding his own justice

Prosecutor: He wanted the university to feel his pain. And the more he could hurt them by shooting anybody, the better he would feel.

Sheila Young: When I went up and sat in the courtroom I didn’t like it. I didn’t like the feeling that it brought me. I didn’t like the attitude that it seemed like he had.

In a Cleveland courtroom, the family of Norman Wallace came face to face with his killer... but they fought the urge to hate the man who took his life. In fact they said if he was convicted they did not want to see him executed for his crimes

Young: I think god removed a lot of that anger and bitterness and you know just wanting to really lash out on him.

Halder’s defense lawyers knew it would be very difficult to get a jury and judge to be as sympathetic.

Rob Stafford, Dateline correspondent: More than 100 witnesses against him, more than a thousand pieces of evidence. Your client’s caught on tape pulling the trigger, right?

Defense attorney: Right.

Stafford: So what do you hope to do for this man?

Defense attorney: It was just outright trying to save his life.

But their client didn’t make it easy for them to prepare a defense, often barking orders at them.

Defense attorney: “Did you get my two cent stamps today?” (chuckles) Like I probably got that request from him, you know, 30 times.

Stafford: You’re trying to save his life, but right away, you wanna strangle this guy?

Defense attorney: If we followed all his directions, we would never be working on the case.

We got a taste of what the defense was up against when we sat down with Halder in the jail where he waited out the trial

Stafford: Your attorney says you’re crazy.

Biswanath Halder: That’s what he says.

Stafford: What do you say? Are you crazy?

Halder: No. I don’t say that.

With a jet black toupee on his head, and a big box of legal documents by his side, Halder was keen to tell his story. He says he first came to this country in 1969 — a whiz kid computer programmer from India.

Stafford: You came here thinking you’re going to start your own business?

Halder: Yeah.

Stafford: You were gonna build something?

Halder: Yeah.

But Halder’s American dream turned into a nightmare when he lost his job and started drinking.

Stafford: How much are you drinking?

Halder: It started out maybe small. Later on it became heavy.

Stafford: And are you intoxicated every day of the week?

Halder: Yeah.

In mid-life Halder says he pulled himself together, graduating with an MBA from Case Western Reserve University. He says he had big plans — a business model that would earn him millions — but that all changed when someone hacked into his computer and deleted thousands of his files.

Stafford: What did you lose that day?

Halder: Everything.

And to this day Halder’s convinced Shawn Miller masterminded the break into his computer.

Halder: He’s a lowlife. He wants to create trouble.

Trouble was something Halder was determined to bring to Miller. He says he spent three years badgering the university, local police, even the FBI to punish Miller. But nothing happened. When his lawsuit failed too, Halder says he decided to punish Miller himself. And not just Miller. He wanted to punish the universityhe thought was protecting Miller.

Halder: I was scared. I was angry. But I had to do it. I didn’t have a choice. I tried everything else.

And Halder admitted he had carefully planned the whole thing. In a calm matter of fact manner, he described, practicing his aim at a shooting range, even loading his arsenal the night before the attack.

Halder: It looked to me that I had more than 800 rounds.

Stafford: More than 800 rounds of ammunition.

Halder: Yeah. But I needed maybe 400.

Stafford: Why do you need 400 rounds of ammunition?

Halder: To fill all the magazines.

He told us about driving to the school that day and showed us the pose he took while shooting. He says he was consumed by anger and that he was firing at anyone he came across.

Stafford: What’s it feel like to go from target practice with a paper target to shooting at live human beings?

Halder: It was terrifying.

Stafford: What were you afraid of?

Halder: Afraid of my life.

Hard as it is to believe, Halder said he did not stop to think about the harm he was causing to other people’s lives.

Halder: I don’t know who I shot.

Stafford: You shot Norman Wallace. Do you remember looking at him when you shot him?

Halder: No. I had no idea who Wallace is. You’re keep on bringing up the name Wallace. I—

Stafford: Norman Wallace.

Halder: I— (overtalk)

Stafford: It’s not just a name. He—

Halder: Yeah.

Stafford: —he’s a victim. He’s—

Halder: of course.

Stafford: --your victim.

Halder: Not at all.

Stafford: Norman Wallace was the pride and joy of his family.

Halder: Yeah.

Stafford: Do you have any idea what you took away from his family that day?

Halder: I did not take away anything from his—

Stafford: What are you talking about? He’s—

Halder: It was—

Stafford: —he’s gone.

Incredibly Halder argued he was not to blame for Norman’s death because if Case Western had disciplined Shawn Miller, Norman Wallace would still be alive.

Stafford: What you don’t get from you is any sense that you have any regret, any remorse for pulling the trigger that day.

Halder: I do regret everything that I did. If I go back I will do things entirely differently.

But what Halder said he’d do differently astounded us. Remember Halder’s rampage occurred three years after his computer was hacked into.

Halder: I would definitely not wait for three years.

Stafford: You would’ve done it sooner.

Halder: Yup.

Stafford: Go in there guns blazing?

But the tables were about to turn on Biswanath Halder. Would this man who had shown no remorse for taking a life, face the same fate as his victim?

Defense attorney (in court): We are truly truly sorry for what happened to Norman Wallace that day.

It was a highly unusual courtroom tactic. Biswanath Halder’s defense team openly admitted what he had done but they begged the jury to convict Halder on lesser charges arguing his actions were not those of a ruthless killer intent on mass murder.

Defense attorney: He’s a bumbling mentally-ill little man who was totally obsessed with the belief that Case Western Reserve University had conspired to attack him.

What’s more, the defense argued the tape proved their point: It showed Halder running scared from the SWAT team, desperate to get out of the building and could not even see.

Defense attorney: He breaks in the back door, loses his glasses. He suffers from glaucoma. So he’s now, in effect, blind. He cannot see anything that’s going on. He’s shooting at shadow. He’s like a little mouse in the maze.

But the jury didn’t buy it. They found Halder guilty on every single charge—murder, attempted mass murder and kidnapping. The quick verdict and possibility of execution finally grabbed Halder’s attention.

Rob Stafford, Dateline correspondent: Is he afraid to die? Is he afraid of the death penalty?

Defense attorney: It finally dawned on him that he might have a problem here.

Now it was time for the penalty phase of the trial and the real work of Halder’s attorneys began. Through the testimony of various witnesses, they painted a picture for the jury of a mentally-ill man, living in a campus attic.

Robert Stein: Frankly, my impression was something was really wrong with him.

Dr. Fabian: He could not conform his behavior to the requirements of the law due to his mental illness.

But was it enough to save his life? The jurors struggled to agree on a sentence, sending two notes to the judge that they were deadlocked. But the next morning they had a decision. As usual, Halder’s lawyers showed more emotion than he did.

Defense attorney: I said many rosaries during that entire deliberation process. And the power of prayer—you can attribute it to whatever you want—I think this—this may have been a little bit of a saving grace here.

The jury decided that Biswanith Halder’s life should be spared. A few weeks later he was sentenced to life in prison.

As the courtroom doors closed on Halder for the last time, the people who survived that day finally felt they could close the door on an afternoon of violence and terror.

George Klippel: I’m not going to allow him to take any more emotion or energy away from me.

Officer Bill Johnson: He’s now behind bars and he’ll be there for the rest of his life. But I’m saddened that three people were shot because of him.

And the family of the young man who was killed hoped Norman Wallace would finally be remembered less for how he had died, and more for how he had lived.

David Wallace: His number one scripture was ‘Do unto others as you want done unto you.’ Norman lived that and believed it.

Corrie Wallace: He was just a beautiful person. He really was. He was special.

Angela Wallace: I think Norman would want people to just live their dreams. And to not be afraid.

At his sentencing in February, Biswanath Halder spoke for 30-minutes, again blaming the university for his violence. But the judge insisted that Halder apologize to Norman Wallace’s family... which he finally did, saying, “It’s a terrible tragedy and I’m exceptionally sorry.”

Dateline wires the home of a volunteer, Jenny, from top to bottom with hidden cameras. Then she called repairmen to her house for a simple problem we created as a test with Jenny's pool. NBC's Chris Hansen reports.